US10736207B1 - Canceling magnetic pickup using three-dimensional wiring assembly - Google Patents

Abstract

A wiring assembly includes a differential input port, a differential output port, and first and second pairs of electrical conductors. The differential input port is configured to receive a differential signal from a sensor at a first end of the wiring assembly. The differential output port is configured to output the differential signal at a second end of the wiring assembly. The first and second pairs of electrical conductors are laid out in a three-dimensional (3D) crossover configuration relative to one another and configured to conduct the differential signal from the first end to the second end, and to cancel pickup of a magnetic field by the wiring assembly. The electrical conductors of each pair are connected to one another at the first end and at the second end.

Description

FIELD OF THE INVENTION

The present invention relates generally to noise and interference reduction in electronic systems, and particularly to methods and systems for reducing parasitic voltage induced in magnetic position tracking systems.

BACKGROUND OF THE INVENTION

Some electronic systems, such as magnetic position tracking systems, conduct electrical signals between an intra-body probe and a controller. The electrical signals are sometimes prone to parasitic voltage induced in the presence of magnetic fields. Various techniques may be used for improving the immunity of electronic systems to induced parasitic voltage.

For example, U.S. Pat. No. 5,371,469 describes a constant current loop measuring system for measuring a characteristic of an environment. The system comprises a first impedance positioned in the environment, a second impedance coupled in series with said first impedance and a parasitic impedance electrically coupled to the first and second impedances. A current generating device, electrically coupled in series with the first and second impedances, provides a constant current through the first and second impedances to produce first and second voltages across the first and second impedances, respectively, and a parasitic voltage across the parasitic impedance. A high impedance voltage measuring device measures a voltage difference between the first and second voltages independent of the parasitic voltage to produce a characteristic voltage representative of the characteristic of the environment.

U.S. Patent Application Publication 2014/0113828 describes electrical, mechanical, computing, and/or other devices that include components formed of extremely low resistance (ELR) materials, including, but not limited to, modified ELR materials, layered ELR materials, and new ELR materials.

SUMMARY OF THE INVENTION

An embodiment of the present invention that is described herein provides a wiring assembly including a differential input port, a differential output port, and first and second pairs of electrical conductors. The differential input port is configured to receive a differential signal from a sensor at a first end of the wiring assembly. The differential output port is configured to output the differential signal at a second end of the wiring assembly. The first and second pairs of electrical conductors are laid out in a three-dimensional (3D) crossover configuration relative to one another and configured to conduct the differential signal from the first end to the second end, and to cancel pickup of a magnetic field by the wiring assembly. The electrical conductors of each pair are connected to one another at the first end and at the second end.

In some embodiments, the first pair includes first and second electrical conductors and the second pair includes third and fourth electrical conductors. The wiring assembly includes four sections laid out along a longitudinal axis of the wiring assembly. The first electrical conductor is laid out at an upper right section, the second electrical conductor is laid out at a lower left section, the third electrical conductor is laid out at an upper left section, and the fourth electrical conductor is laid out at a lower right section. In other embodiments, the wiring assembly includes a circuit board (CB) having a substrate, a first layer disposed on a first side of the substrate and a second layer disposed on a second side of the substrate. The first and third electrical conductors include first and third electrical traces formed in parallel to one another in the first layer. The second and fourth electrical conductors include second and fourth electrical traces formed in parallel to one another in the second layer. The first and fourth electrical traces face one another across the substrate, and the second and third electrical traces face one another across the substrate.

In an embodiment, the wiring assembly includes a circuit board (CB) having a substrate, a first layer disposed on a first side of the substrate and a second layer disposed on a second side of the substrate. The electrical conductors of the first and second pairs include electrical traces formed in the CB. In another embodiment, the differential output port is configured to electrically connect to a differential amplifier, for amplifying the differential signal.

There is additionally provided, in accordance with an embodiment of the present invention, a method for producing a wiring assembly, the method includes providing a differential input port for receiving a differential signal from a sensor at a first end of the wiring assembly. A differential output port is provided for outputting the differential signal at a second end of the wiring assembly. First and second pairs of electrical conductors are laid out, between the first end and the second end, in a three-dimensional (3D) crossover configuration relative to one another, and each pair of the electrical conductors in connected to one another at the first end and at the second end. Each pair of the electrical conductors is coupled to the differential input port at the first end, and to the differential output port at the second end.

The present invention will be more fully understood from the following detailed description of the embodiments thereof, taken together with the drawings in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic, pictorial illustration of a catheter-based magnetic position-tracking and ablation system, in accordance with an embodiment of the present invention;

FIG. 2 is a schematic block diagram of a wiring assembly for canceling magnetic pickup noise, in accordance with an embodiment of the present invention; and

FIG. 3 is a schematic, pictorial illustration of a three-dimensional (3D) wiring assembly for canceling magnetic pickup noise, in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTSOverview

Embodiments of the present invention that are described hereinbelow provide improved techniques for reducing parasitic voltage, which may be induced in a wiring assembly by an alternating magnetic field. Alternating magnetic fields are sometimes used in medical applications such as for tracking the position of a medical probe in an organ of the body.

In some embodiments, a magnetic position sensor is coupled to a distal end of a medical probe, and is configured to produce, in response to an alternating magnetic field of a position tracking system, a differential signal indicative of the position of the distal end in a patient body.

In some embodiments, the medical probe comprises a wiring assembly, which is configured to conduct the differential signal from the position sensor to a differential amplifier, coupled to the proximal end of the wiring assembly.

In some embodiments, the wiring assembly comprises a differential input port, configured to receive the differential signal at the distal end of the wiring assembly, and a differential output port, configured to output the differential signal to the amplifier.

In some embodiments, the wiring assembly further comprises a circuit board (CB) having two pairs of electrical traces configured to conduct the differential signal between the proximal and distal ends of the wiring assembly. The two pairs are patterned in a three-dimensional (3D) crossover configuration, relative to one another, along a longitudinal axis of the wiring assembly. The traces in each pair are electrically connected to one another both at the input port and the output port of the wiring assembly. The two pairs of traces are also referred to herein as a first pair and a second pair.

In an example embodiment, the first pair comprises first and second traces, and the second pair comprises third and fourth traces. In the 3D crossover configuration, the first and second traces of the first pair are laid out at the upper left and lower right sides of the CB, respectively, and the third and fourth traces of the second pair are laid out at the upper right and lower left sides of the CB, respectively.

In this configuration, the first and second traces are interconnected, at each of the input and output ports, in a first diagonal connection between the upper left and lower right sides of the CB. Similarly, the third and fourth traces are interconnected, at each port, in a second diagonal between the upper right and lower left sides of the CB. Note that even though the first and second diagonals are spatially crossing one another, the traces along the diagonals are electrically disconnected.

In some embodiments, the configuration of the diagonal connections, as described above, is implemented at the input and output ports of the wiring assembly. In this configuration, the first and second pairs form first and second respective electrically conductive loops having a similar cross-sectional area. Therefore, an approximately equal magnetic flux (produced by the alternating magnetic field of the position tracking system) traverses the first and second loops. The two loops, however, have opposite orientations (i.e., one has a clockwise orientation and the other has a counter-clockwise orientation). Therefore, the parasitic voltages induced in the two loops by the alternating magnetic field (referred to as first and second parasitic voltages, or first and second magnetic pickups) have similar absolute values but opposite polarities. The first and second parasitic voltages are therefore canceled out or at least reduced significantly at the output port of the wiring assembly.

The disclosed techniques may be used for canceling undesired noise, induced by external magnetic fields in signals received from various types of sensors coupled to a distal end of a medical probe. Moreover, the disclosed techniques may be implemented in any electronic system, e.g., in a magnetic resonance imaging (MRI) system, for protecting electrical signals against interference induced by external magnetic fields.

System Description

FIG. 1 is a schematic, pictorial illustration of a catheter-based magnetic position-tracking andablation system20, in accordance with an embodiment of the present invention.System20 comprises acatheter21, having a shaftdistal end22 that is navigated by aphysician30 into aheart26 of apatient28 via the vascular system. In some embodiments,physician30 inserts shaftdistal end22 through asheath23, while manipulatingdistal end22 using amanipulator32 located at the proximal end ofcatheter21.

Reference is now made to aninset25. In some embodiments,system20 comprises amagnetic sensor51, also referred to herein as a magnetic position tracking sensor orsensor51 for brevity, and anablation catheter50, which are coupled todistal end22.

In the embodiments,catheter21 may be used for various procedures, such as electrophysiological (EP) mapping ofheart26 and for ablating selected tissue ofheart26.

In some embodiments, the proximal end ofcatheter21 is electrically connected to acontrol console24 via electrical leads and/or traces. In an embodiment,console24 comprises aprocessor39 andinterface circuits38, which is configured to exchange signals betweenprocessor39 and various components and assemblies ofsystem20.

In some embodiments,interface circuits38 are configured to receive electrical signals fromcatheter21 and other sensors ofsystem20.Circuits38 are further configured to send electrical signals fromprocessor38 to various components and assemblies ofsystem20, such as applying power viacatheter21 for ablating tissue ofheart26, and for controlling the other components and assemblies ofsystem20.

In some embodiments,system20 comprises multiple (e.g., three)magnetic field generators36, configured to produce alternating magnetic fields.Field generators36 are placed at known positions external topatient28, for example, below a patient table29.

In some embodiments,console24 further comprises adriver circuit34, which is configured to drivemagnetic field generators36, and adisplay27.

During amedical procedure physician30 navigatesdistal end22 ofcatheter21 inheart26 In some embodiments, in response to the magnetic fields irradiated fromfield generators36,magnetic sensor51 is configured to produce a differential electrical signal, also referred to herein as a differential signal or a position signal, indicative of the position ofdistal end22 inheart26.

In some embodiments, based on the differential signal received fromsensor51,processor39 is configured to display, e.g., ondisplay27, the position ofdistal end22 in the coordinate system ofsystem20.

This method of position sensing is implemented, for example, in the CARTO™ system, produced by Biosense Webster Inc. (Irvine, Calif.) and is described in detail in U.S. Pat. Nos. 5,391,199, 6,690,963, 6,484,118, 6,239,724, 6,618,612 and 6,332,089, in PCT Patent Publication WO 96/05768, and in U.S. Patent Application Publications 2002/0065455 A1, 2003/0120150 A1 and 2004/0068178 A1, whose disclosures are all incorporated herein by reference.

Processor39 typically comprises a general-purpose processor, which is programmed in software to carry out the functions described herein. The software may be downloaded to the computer in electronic form, over a network, for example, or it may, alternatively or additionally, be provided and/or stored on non-transitory tangible media, such as magnetic, optical, or electronic memory.

Magnetic Pickup Cancellation Using a Wiring Assembly Having Multiple Traces

FIG. 2 is a schematic block diagram of awiring assembly111 ofcatheter21, in accordance with an embodiment of the present invention. In some embodiments,wiring assembly111 may be implemented incatheter21 for conducting the aforementioned differential signal betweensensor51 andconsole24, via electrical readout circuitry such as a differential amplifier, referred to herein as anamplifier52.

In some embodiments,wiring assembly111 comprises adifferential input port100, which is configured to receive the differential signal fromsensor51, positioned at the distal end ofwiring assembly111. In some embodiments,wiring assembly111 further comprises adifferential output port101, which is configured to output the differential signal received frominput port100, toamplifier52, positioned at the proximal end ofwiring assembly111.

In some embodiments,amplifier52 may be fitted at any suitable position alongcatheter21. For example,amplifier52 may be fitted inmanipulator32 held byphysician30, or inconsole24 coupled to the proximal end ofcatheter21.

In some embodiments,input port100 comprises input points60aand60b, which are coupled to respective ends of a coil ofsensor51.Output port101 comprises output points62aand62b, which are coupled to respective inputs ofdifferential amplifier52.

In some embodiments,wiring assembly111 comprises a first differential pair of electrical conductors, in the present exampleelectrical traces54aand54b, which are electrically connected betweenports100 and101. In the example configuration ofFIG. 2, trace54ais electrically connected betweeninput point60aandoutput point62a, and trace54bis electrically connected betweeninput point60bandoutput point62b.

In some embodiments, traces54aand54bare configured to conduct the aforementioned differential signal fromsensor51, viaports100 and101, toamplifier52. As described inFIG. 1 above,field generators36 produce one or more alternating magnetic fields in the body ofpatient28, shown asfield lines48 traversingwiring assembly111.

When wiringassembly111 conducts the differential signal, the magnetic fields may induce a first parasitic voltage in a clockwise (CW) loop, shown byarrows88. Note that the value of the induced first parasitic voltage depends, inter-alia, on the magnitude and direction of the magnetic field traversing the loop, and has a predefined polarity (e.g., positive) in the CW loop. The first parasitic voltage may distort the differential signal at the inputs ofamplifier52, and therefore, may reduce the accuracy and overall performance of the magnetic position-tracking system.

In the context of the present invention, and in the claims, the terms “magnetic pickup,” “magnetic field pickup,” “magnetic noise pickup” and “parasitic voltage” are used interchangeably and refer to undesired voltage induced by the magnetic field traversingwiring assembly111 at any direction not parallel to a Y-Z plane ofFIG. 2. As described above, the parasitic voltage may interfere with the differential signal produced bysensor51 and, therefore, may reduce the position tracking performance ofsystem20.

In some embodiments,wiring assembly111 further comprises a second pair of electrical conductors, in the present exampleelectrical traces55aand55b, also configured to conduct the differential signal betweenports100 and101. In some embodiments, trace55ais electrically connected betweeninput point60aandoutput point62a, and trace55bis electrically connected betweeninput point60bandoutput point62b.

In some embodiments, traces54aand55aare electrically connected to one another atinput port60aand atoutput port62a. Similarly, trace54band55bare electrically connected to one another atinput port60band atoutput port62b.

In some embodiments, when conducting the differential signal,field lines48 may induce in wiring assembly111 a second parasitic voltage having a negative polarity in a counterclockwise (CCW) loop, shown byarrows99. In an embodiment,wiring assembly111 is designed such that the areas within the CW and CCW loops are substantially similar. As a result, the first and second parasitic voltages may have substantially similar absolute values but opposite polarities. Therefore, in this configuration, the first and second parasitic voltages cancel one another.

Thus, when conducting the differential signal betweensensor51 andamplifier52 in the presence of traversing magnetic fields,wiring assembly111 is configured to cancel out the induced parasitic voltage.

In this embodiment, when wiringassembly111 conducts the differential signal betweensensor51 andamplifier52, the first and second parasitic voltages cancel one another, thus reducing the interference on the differential signal produced bysensor51.

For example,sensor51 may produce a suitable differential signal between tens of microvolts and tens of millivolts. In response to an alternating magnetic field, for example, between an order of micro-Henry and an order of Henry, the first and second loops may induce respective magnetic pickups between tens of microvolts and tens of millivolts.

In other embodiments, the first and second pairs described above, may comprise any other suitable type of electrical conductors, such as wires or leads. The configuration of a wiring assembly is also described, for example, in U.S. patent application Ser. No. 16/018,614, which is assigned to the assignee of the present patent application and whose disclosure is incorporated herein by reference.

This particular configuration ofwiring assembly111 is shown by way of example, in order to illustrate certain problems, such as induced parasitic voltage addressed by embodiments of the present invention, and to demonstrate the application of these embodiments in enhancing the performance ofsystem20. Embodiments of the present invention, however, are by no means limited to this specific sort of example configuration, and the principles described herein may similarly be applied to other sorts of wiring assemblies so as to cancel out magnetic pickup in other sorts of electronic systems operating in the presence of various types of traversing external fields.

Canceling Magnetic Pickup Using a 3D Wiring Assembly

FIG. 3 is a schematic, pictorial illustration of awiring assembly200, in accordance with an embodiment of the present invention. In some embodiments,wiring assembly200 implements a three-dimensional (3D) configuration version ofwiring assembly111 ofFIG. 2 above.

In some embodiments,wiring assembly200 may be integrated incatheter21 so as to cancel out magnetic pickup noise, induced by the magnetic fields as described above, whencatheter21 conducts the aforementioned differential signals betweensensor51 andamplifier52. Additionally or alternatively,wiring assembly200 is configured to conduct electrical signals between any other components ofsystem20 that may be affected by an external magnetic field.

In some embodiments,wiring assembly200 comprises a circuit board (CB)210, laid out without loss of generality in an x-y plane of the xyz coordinate system ofFIG. 3.

In some embodiments,CB210 comprises asubstrate204, typically made from multi-layered epoxy, reinforced by pre-impregnated (“prepreg”) weave of glass fibers, or from any other suitable materials.

Reference is now made to aninset208, which is asectional view216 ofwiring assembly200 in an X-Z plane of the XYZ coordinate system.

For the sake of conceptual clarity,sectional view216 ofwiring assembly200, as well asinset208 are divided into four virtual sections along the Y-axis, which is the longitudinal axis ofwiring assembly200. The four virtual sections comprise an upper left (UL) section, an upper right (UR) section, a lower left (LL) section, and a lower right (LR) section. The four sections are separated from one another by dashedlines215 and217, and each section is confined within the frame ofinset208. In the example ofFIG. 3, all sections have a similar area, but in other embodiments, at least one of the sections may have a different area.

In some embodiments,CB210 comprises any suitable polymer-basedlayers202 and206, each of which is made from one or more sub-layers, formed, respectively, on anupper surface212 and alower surface214 ofsubstrate204. Note thatsubstrate204 andlayers202 and206 are electrically insulating.

Reference is made again to an isometric view ofwiring assembly200 shown inFIG. 3. In some embodiments,wiring assembly200 comprises two pairs of electrical conductors, laid out along Y axis. The first pair compriseselectrical traces220aand220b, and the second pair compriseselectrical traces230aand230b.

In some embodiments, the first and second pairs of electrical traces are laid out in a three-dimensional (3D) crossover configuration relative to one another. In this configuration, the traces of each pair are laid out in the diagonal sections ofinset208.

For example,electrical traces220aand220bare laid out, respectively, in the UL and LR sections ofinset208, which are diagonal to one another. Similarly,electrical traces230aand230bare laid out, respectively, in the UR and LL sections ofinset208, which are also diagonal to one another. Therefore, the two pairs of electrical conductors are laid out in the 3D crossover configuration relative to one another.

In some embodiments, the electrical traces are patterned inlayers202 and206, and therefore, are electrically insulated from one another bysubstrate204 andlayers202 and206.

In some embodiments,electrical traces220aand230aof the first and second respective pairs, are disposed inlayer202, andelectrical traces220band230bof the first and second respective pairs, are disposed inlayer206.

In some embodiments, adjacent electrical traces along X-axis or Z-axis are positioned within a predefined distance from one another. For example, a first, substantially similar, distance betweentraces220aand230band betweentraces230aand220b. Similarly, a second, substantially similar, distance betweentraces220aand230aand betweentraces220band230b. In an embodiment, the first and second distances are substantially similar to one another. In other words, adjacent electrical traces along X-axis and Z-axis are positioned within a similar distance from one another.

In some embodiments, when implemented incatheter21, traces220a,220b,230aand230bofwiring assembly200 are electrically coupled to sensor51 (not shown) at adistal end280 and to amplifier52 (not shown) at aproximal end270, using any suitable input and output ports, such asinput port100 andoutput port101 depicted inFIG. 2 above.

Reference is made again toinset208. When applying the differential signal totraces220a,220b,230aand230b, and the aforementioned alternating magnetic fields produced byfield generators36,wiring assembly200 has multiple loops similar to the CW and CCW loops described in inFIG. 2 above.

As shown insectional view216 ofinset208, alternating magnetic fields, referred to herein as Bx and Bz, are applied towiring assembly200 in X-axis and Z-axis, respectively. Note that Bx and Bz are provided by way of example for the sake of clarity. In EP procedures, however, the direction of the actual alternating magnetic field depends, inter-alia, on the configuration offield generators36 and the orientation ofdistal end22. Therefore, the direction of the actual alternating magnetic field applied towiring assembly200 may be any combination of Bx and Bz, referred to herein as Bxz and also shown ininset208.

In some embodiments, the configuration ofwiring assembly200 forms, in response to the differential signal and magnetic fields, a first pair ofloops272 and274 along Z-axis, and a second pair ofloops276 and278 along X-axis. Note that the field lines of alternating magnetic field Bz are traversing bothloops272 and274. In this configuration,loops272 and274 correspond, respectively, to the CW and CCW loops depicted inFIG. 2 above. In other words, when conducting the differential signal produced bysensor51, in response to alternating magnetic field Bz,loops272 and274 produce parasitic voltages having similar absolute values but opposite polarities.

In these embodiments, based onloops272 and274,wiring assembly200 is configured to cancel out the parasitic voltage induced in response to alternating magnetic field Bz.

Similarly, field lines of alternating magnetic field Bx are traversing bothloops276 and278. In this configuration,loops276 and278 correspond, respectively, to the CW and CCW loops ofFIG. 2 above. In some embodiments, based onloops276 and278,wiring assembly200 is configured to cancel out the parasitic voltage induced in response to alternating magnetic field Bx.

Moreover, as described above, a combination of the CW and CCW loops is configured to cancel out any combination of magnetic fields. Therefore, in accordance with the embodiments described above,loops272,274,276 and276 are further configured to cancel out any parasitic voltage induce in response to alternating magnetic field Bxz or any other alternating magnetic field formed as a combination of Bx and Bz.

Reference is made again to the isometric view ofFIG. 3. In some embodiments,wiring assembly200 comprises electrical conductors, such asleads240 and242 positioned atproximal end270 anddistal end280, respectively.Leads240 and242 are electrically connecting betweenelectrical traces220aand220bof the first pair.Wiring assembly200 comprises additional electrical conductors, such asleads250 and252, electrically connecting betweenelectrical traces230aand230bof the second pair, atproximal end270 anddistal end280, respectively.

In some embodiments, leads240 and250 may be connected toamplifier52, and leads242 and252 may be connected tosensor51, both shown inFIG. 2 above. For evaluating the performance ofwiring assembly200 in canceling magnetic pickup, the inventors made provisional connections byleads240,242,250 and252, and applied the aforementioned differential signal and alternating magnetic fields, such as Bx and Bz, towiring assembly200. In one such experiment a reduction of 20 dB in the noise level was measured.

In these performance evaluation embodiments, leads240,242,250 and252 have been used only for testing, and are therefore shown as dashed lines in the isometric view ofwiring assembly200, shown inFIG. 3.

In other embodiments, the traces ofwiring assembly200 may be arranged in a different configuration so as to cancel out parasitic voltage caused by alternating magnetic fields in selected directions. For example, trace220bof the first pair may be disposed instead oftrace230aof the second pair, and vice-versa. In other words, traces220aand220bare disposed inlayer202 and traces230aand230bare disposed inlayer206.

In this configuration, the wiring assembly may have two diagonal loops, and therefore is configured to cancel out parasitic voltage induced by alternating magnetic field Bz, whereas the parasitic voltage induced by alternating magnetic field Bx will not be canceled.

In another example configuration, traces220aand220bare disposed, respectively, in the UR and LR sections ofwiring assembly200, and traces230aand230bare disposed, respectively, in the UL and LL sections ofwiring assembly200.

In this configuration,wiring assembly200 may have two diagonal loops, and therefore is configured to cancel out parasitic voltage induced by alternating magnetic field Bx, whereas the parasitic voltage induced by alternating magnetic field Bz will not be canceled.

The particular configuration ofwiring assembly200 is shown by way of example, in order to illustrate certain problems that are addressed by embodiments of the present invention and to demonstrate the application of these embodiments in enhancing the performance of the magnetic position tracking system comprised insystem20. Embodiments of the present invention, however, are by no means limited to this specific sort of example wiring assembly and magnetic position tracking system, and the principles described herein may similarly be applied to other sorts of electronic systems operating under external alternating magnetic and/or electrical fields.

Although the embodiments described herein mainly address magnetic position tracking systems used in minimally-invasive medical application, the methods and systems described herein can also be used in other applications, such as in any transmission of low amplitude differential signal affected by external magnetic fields.

It will thus be appreciated that the embodiments described above are cited by way of example, and that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention includes both combinations and sub-combinations of the various features described hereinabove, as well as variations and modifications thereof which would occur to persons skilled in the art upon reading the foregoing description and which are not disclosed in the prior art. Documents incorporated by reference in the present patent application are to be considered an integral part of the application except that to the extent any terms are defined in these incorporated documents in a manner that conflicts with the definitions made explicitly or implicitly in the present specification, only the definitions in the present specification should be considered.

Claims (10)

The invention claimed is:

1. A wiring assembly, comprising:

a differential input port, configured to receive a differential signal from a sensor at a first end of the wiring assembly;

a differential output port, configured to output the differential signal at a second end of the wiring assembly; and

first and second pairs of electrical conductors, laid out in a three-dimensional (3D) crossover configuration relative to one another and configured to conduct the differential signal from the first end to the second end, and to cancel pickup of a magnetic field by the wiring assembly, wherein the electrical conductors of each pair are connected to one another at the first end and at the second end, the first and second pairs of electrical conductors form electrically conductive loops having substantially the same cross-sectional areas and arranged such that parasitic voltages induced in the two loops are equal in value but of opposite polarity.

2. The wiring assembly according toclaim 1, wherein the first pair comprises first and second electrical conductors and the second pair comprises third and fourth electrical conductors, wherein the wiring assembly comprises four sections laid out along a longitudinal axis of the wiring assembly, and wherein the first electrical conductor is laid out at an upper right section, the second electrical conductor is laid out at a lower left section, the third electrical conductor is laid out at an upper left section, and the fourth electrical conductor is laid out at a lower right section.

3. The wiring assembly according toclaim 2, and comprising a circuit board (CB) having a substrate, a first layer disposed on a first side of the substrate and a second layer disposed on a second side of the substrate,

wherein the first and third electrical conductors comprise first and third electrical traces formed in parallel to one another in the first layer,

wherein the second and fourth electrical conductors comprise second and fourth electrical traces formed in parallel to one another in the second layer,

and wherein the first and fourth electrical traces face one another across the substrate, and the second and third electrical traces face one another across the substrate.

4. The wiring assembly according toclaim 1, and comprising a circuit board (CB) having a substrate, a first layer disposed on a first side of the substrate and a second layer disposed on a second side of the substrate, wherein the electrical conductors of the first and second pairs comprise electrical traces formed in the CB.

5. The wiring assembly according toclaim 1, wherein the differential output port is configured to electrically connect to a differential amplifier, for amplifying the differential signal.

6. A method for producing a wiring assembly, the method comprising:

providing a differential input port, for receiving a differential signal from a sensor at a first end of the wiring assembly;

providing a differential output port, for outputting the differential signal at a second end of the wiring assembly;

laying out, between the first end and the second end, first and second pairs of electrical conductors in a three-dimensional (3D) crossover configuration relative to one another, and connecting each pair of the electrical conductors to one another at the first end and at the second end; and

coupling each pair of the electrical conductors to the differential input port at the first end, and to the differential output port at the second end, wherein the first and second pairs of electrical conductors form electrically conductive loops having substantially the same cross-sectional areas and arranged such that parasitic voltages induced in the two loops are equal in value but of opposite polarity.

7. The method according toclaim 6, wherein the first pair comprises first and second electrical conductors and the second pair comprises third and fourth electrical conductors, wherein the wiring assembly comprises four sections laid out along a longitudinal axis of the wiring assembly, and wherein laying out the first and second pairs comprises, laying out: (a) the first electrical conductor at an upper right section, (b) the second electrical conductor at a lower left section, (c) the third electrical conductor at an upper left section, and (d) the fourth electrical conductor at a lower right section.

8. The method according toclaim 7, and comprising providing a circuit board (CB) having a substrate, disposing a first layer on a first side of the substrate and disposing a second layer on a second side of the substrate,

wherein laying out the first and third electrical conductors comprise forming first and third electrical traces in parallel to one another in the first layer,

wherein laying out the second and fourth electrical conductors comprise forming second and fourth electrical traces in parallel to one another in the second layer,

and wherein the first and fourth electrical traces face one another across the substrate, and the second and third electrical traces face one another across the substrate.

9. The method according toclaim 6, and comprising providing a circuit board (CB) having a substrate, disposing a first layer on a first side of the substrate and disposing a second layer on a second side of the substrate, wherein laying out the electrical conductors of the first and second pairs comprises forming electrical traces in the CB.

10. The method according toclaim 6, and comprising electrically connecting the differential output port to a differential amplifier for amplifying the differential signal.

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